Variable eccentricity driver



March 10, 1970 M. A. PEARSON 3,499,347

VARIABLE ECCENTRICI'IY DRIVER Filed May 29, 1968 2 Sheets-Sheet 1INVENTOR MELVIN A. PEARSON ATTOR NEYS March 10, 1970 M. A. PEARSON3,499,347

VARIABLE ECCENTRICITY DRIVER Filed May 29, 1968 2 Sheets-Sheet 2INVENTOR MELVIN A. PEARSON i/mz 65 x Maw ATTORNEYS United States Patent3,499,347 VARIABLE ECCENTRICITY DRIVER Melvin A. Pearson, 1431 E. DudleyAve., Indianapolis, Ind. 46227 Filed May 29, 1968, Ser. No. 733,125 Int.Cl. F16h 53/00 US. Cl. 74568 18 Claims ABSTRACT OF THE DISCLOSURE Avariable eccentricity driver comprising a cam shaft, a drive camjournalled on an eccentric portion of the cam shaft, and means forselectively positioning the drive cam about the axis of the eccentricportion. The positioning means includes a member connected to the drivecam and arranged forcontrolled rocking movement about the axis of thecam shaft. The drive cam is ideally suited for driving the piston of avariable stroke pump or other follower means.

It is a primary object of my invention to provide a variableeccentricity driver which is simple in construction and, yet, effectivefor imparting a reciprocatory or oscillatory movement to the drivenelement of a plurality of different types of apparatus. My driver may becharacterized as a cam shaft having a selectively variable eccentricity.

Another object of my invention is to provide such a driver comprising ashaft, a cylindrical element eccentrically mounted on the shaft forrotation therewith with its axis parallel to the axis of the shaft, adrive cam journalled on the outer peripheral surface of the element andmeans for selectively positioning the drive cam about the axis of theelement. I prefer that this last-mentioned means comprise a membermounted on the shaft for rocking movement relative thereto, meansproviding a driving connection between the drive cam and the member andcontrol means for rocking the member about the shaft. My preferredcontrol means is arranged smoothly, i.e., without a step-by-step motion,to rock the member about the shaft.

Still another object of my invention is to provide such a controlmeans'comprising a pair of members mounted on the shaft for rotationtherewith, the members being arranged for relative axial movement, aradially extending pin carried by one of the members and the other ofthe members being formed with an elongated slot for slidably engagingthe pin, the slot being spirally inclined about the axis of the shaft.Preferably, such members will be telescopically related sleeves, thesleeves being telescopically mounted on the shaft and one of the sleevesbeing operatively connected to the shaft so that such relative axialmovement produces a rocking movement of the other sleeve relative to theshaft.

A further object of my invention is to provide such a driver comprisingmeans for drivingly connecting the control means to the drive cam, theconnecting means comprising means operatively connected to the controlmeans and providing guide means extending outwardly from the shaft andslide means carried by the drive cam and cooperatively engaged with theguide means. In a preferred embodiment of my invention, this connectingmeans comprises a disc carried by the shaft and operatively connected tothe control means, the disc having an outwardly extending, elongatedslot formed therein, and the slide means comprises a pin rigidly mountedon the drive cam and arranged slidably to engage the slot.

Other objects and features of the present invention will become apparentas this description proceeds.

3,499,347 Patented Mar. 10, 1970 To the accomplishment of the above andrelated objects, my invention may be embodied in the forms illustratedin the accompanying drawings, attention being called to the fact,however, that the drawings are illustrative only, and that change may bemade in the specific constructions illustrated and described, so long asthe scope of the appended claims is not violated.

In the drawings:

FIG. 1 is a fragmentary sectional view showing a variable speed drivesystem embodying my variable eccentricity driver;

FIG. 2 is an exploded perspective view of my driver;

FIG. 3 is a fragmentary sectional view taken from FIG. 1 generally alongthe line 33; and

FIG. 4 is a sectional view of a pumping system embodying my driver.

Referring now to the drawings, and particularly to FIG. 2, it will beseen that I have illustrated a driver, indicated generally by thereference numeral 10, comprising a shaft 12 on which a bearing and stopcollar 14 is mounted, the collar being secured to the shaft by meanssuch as the illustrated set screw 16. A radially outwardly extending pin18 is rigidly mounted on the shaft 12 and a pair of spaced-apart,transaxially extending openings 20, 22 is provided in the shaft, theseopenings preferably being threaded. The shaft 12 serves as the mainsupporting shaft for the rest of the elements of my driver.

A disc member 24 having a centrally disposed hub portion 26 thereon anda centrally located and axially extending bore 28 therein is journalmounted on the shaft 12. Specifically, the bore 28 through the hubportion 26 is enlarged so that the hub portion is peripherally disposedabout the collar 14 to define an annular space therebetween. A sleeve 30having a reduced end portion 32 is mounted on the shaft 12 with thereduced end portion inserted into the annular space defined by the hub26 and the collar 14. The sleeve 30 and the disc member 24 are rigidlyfastened together by means such as the illustrated set screw 34 whichextends through the hub portion to engage the reduced portion 32. Thedisc member 24 and the sleeve 30, therefore, are secured together forrocking movement relative to the shaft 12 and collar 14. The member 24is restrained from movement axially in the direction of the arrow 36because the diameter of the collar 14 is greater than the smallestdiameter portion of the bore 28 through the member 24. The disc member24 is also restrained from axial movement in the direction opposite tothe arrow 36 by means of the illustrated eccentric element 38 which ismounted on the shaft 12 and which is secured in position on the shaft bymeans of a set screw 40 which engages the opening 22. The main functionof this eccentn'c element 38 will be more fully explained hereinafter.

The sleeve 30 is also restrained against axial movement in the directionopposite to the arrow 36 by engagement of the face 42 thereof with thehub portion 26.

Another eccentric element 42 is mounted on the shaft 12 for rotationtherewith, this eccentric element being secured in position on the shaftby means such as the illustrated set screw 44 which engages the opening20. In the illustrative embodiment, the eccentric elements 38, 42 areidentical with cylindrical outer peripheral surfaces of equal diameter,the axes of these surfaces being parallel to the axis of the shaft 12.Further, in the illustrative embodiment, the elements 38, 42 areradially oppositely disposed on the shaft 12, i.e., the point of maximumeccentricity on the element 38 is displaced from the point of maximumeccentricity on the element 42. A drive cam 46, 48 is journalled on theouter peripheral surface of each eccentric element 38, 42, these camsbeing separated by a disc 50 which is journalled on the shaft 12 andwhich is disposed between the eccentric elements 38, 42. A retainermeans 52 having a flange portion 54 and a hub portion 56 is journalmounted on the shaft 12 and arranged to prevent axial movement of thecam 48 in a direction opposite to the arrow 36. Any suitable means maybe used to hold retainer means 52 against axial movement relative to theshaft 12.

It will be apparent from FIG. 2 that the shaft 12 extends axiallythrough the bore of the sleeve 30, the bore 28 of the disc member 24,the opening 58 in the eccentric element 38, the opening 60 in the disc50, the' opening 62 in the eccentric element 42, and the central bore 64in the retainer means 52. It will further be apparent that each cam 46,48 is provided with an axially extending, eccentric cylindrical opening66, 68, the inner peripheral surface of which is in bearing contact withthe outer peripheral surface of its associated eccentric element 38, 42.

Each cam 46, 48 carries an axially extending pin 70, 8-8 which, in theillustrative embodiment, has a portion extending outwardly from eachside thereof. One end portion 72 of the pin 70 is slidably engaged in aradially outwardly extending slot 74 in the disc member 24 and the otherend portion 76 of that pin is slidably engaged in a radially outwardlyextending slot 78 in the disc 50. Similarly, one end portion 80 of thepin 88 slidably engages another radially extending slot 82 in the disc50 and the other end portion 84 of that pin slidably engages a radiallyextending slot 86 in the flange 54. It will be understood, however, thatthe engagement of the pin 88 with the slot 86 is merely a matter ofconvenience and the slot 86 is only provided so that the pins 70 and 88can be identical.

It will now be apparent that the pin 70 engages the slot 74 so thatrocking movement of the disc member 24 about the axis of the shaft 12will produce movement of the cam 46 about the axis of the eccentricelement 38. Since the pin 70 is also engaged with the slot 78 and thepin 88 is engaged with the slot 82, such movement of the cam 46 aboutthe axis of the eccentric element 38 will produce movement of the cam 48in the same direction about the axis of the eccentric element 42. Sincethe slots 78, 82 and pins 70, 88 are radially oppositely disposed andsince the eccentric elements 38, 42 are identical and disposed onradially opposite sides of the shaft 12, the amount of radial movementof the cam 48 will be equal to the amount of radial movement of the cam46.

I can mount any number of cams and eccentric elements on a shaft andinterconnect them by means of pins and discs asdescribed above so thatrocking movement of one cam will produce a corresponding rockingmovement of the other cams. Further, I can vary the amount one cam movesrelative to its adjacent cam by selectively positioning the pin carriedby the cam and/ or changing the angle or contour of the slot in the discproviding a driving connection between the cams. For instance, the slots78, 82 need not extend rectilinearly radially outwardly from the centerof the disc 50.

From the above description, it will be apparent that the degree ofeccentricity of the earns 46, 48 relative to the axis of shaft 12 isdependent on the position of the disc member 24 and is infinitelyvariable from zero to a predetermined maximum. I have provided controlmeans, indicated generally by the reference numeral 90, for selectivelyand rockably positioning the member 24 about the axis of the shaft 12.In the illustrative embodiment, the control means 90 comprises a sleeve92 which is disposed telescopically on the shaft 12 and within thesleeve 30, the sleeve 92 being formed with an elongated slot 94 thereinwhich inclines spirally about the axis thereof. The pin 18 is slidablyengaged in this slot 94 so that axial movement of the sleeve 92 in thedirection of the arrow 96 causes the sleeve 92 to rock in the directionof the arrow 98 relative to the shaft 12. Of course, movement of thesleeve 92 in the direction of the arrow 36 causes the sleeve to rock inthe direction opposite to the arrow 98. In order to provide a drivingconnection between the sleeve 92 and the sleeve 30, I have provided aradially outwardly extending pin 100 which is rigidly mounted on thesleeve 92 and which slidably engages an elongated slot 102 which, in theillustrative embodiment, is formed internally in the wall of the sleeve30. Further, I have formed the slot 102 so that it is spirally inclinedabout the axis of the sleeve 30 such that axial movement of the sleeve92 relative to the sleeve 30 will cause the sleeve 30 to rock about itsaxis relative to the sleeve 92. This slot 102 is spirally inclined sothat axial movement of the sleeve 92 in the direction of the arrow 96will produce movement of the sleeve 30 in the direction of the arrow 98relative to the sleeve 92. Thus, the rocking movement of the sleeve 30is in the same direction and, therefore, in addition to the rockingmovement of the sleeve 92. Obviously, the pitch and direction of eitheror both of the slots 94 and 102 may be varied to provide any desiredrelation between the degree of axial movement of sleeve 92 relative toshaft 12 and the resultant degree of r0- tational movement of sleeve 30and member 24.

Since the disc member 24 is rigidly fastened to the sleeve 30 by meansof the set screw 34, movement of the sleeve 30 about the axis of theshaft 12 produces movement of the earns 46, 48 about their respectiveeccentric elements 38, 42.

A radially outwardly and peripherally extending flange 104 is rigidlymounted on the sleeve 92 to provide means for pushing and pulling thesleeve axially on the shaft 12. The axial movement of the sleeve 92 inthe direction of the arrow 36 is limited by a stop 106 which is mountedon the shaft 12 and secured in position by means such as the illustratedset screw 108. In the illustrative embodiment, the stop 106 can bearranged so that, when the sleeve 92 is in the center of its axial pathof movement, the disc member 24 is in the center of its radial extent ofmovement and the axes of the outer peripheral surfaces of the cams 46,48 coincide with the axis of the shaft 12. Thus, movement of the sleeve92 axially from one end of its travel to the other end will move eachcam 46, 48 from its outermost position on one side of the shaft 12 toits outermost position on the radially opposite side of the shaft 12.

While I have illustrated the earns 46, 48 having a cylindrical outerperipheral surface, it will be understood that cams having any desirablecontour may be journalled on the eccentric elements 38, 42 or, for thatmatter, any number of types of driving elements may be mounted on theeccentric elements 38, 42. For that reason, in this description and inthe appended claims, the term drive cam or cam is intended to refer toany type of drive element which may be journal mounted on the eccentricelements 38, 42 for movement toward and away from the axis of the shaft12.

It will be seen that the shaft 12 with the eccentric elements 38, 42mounted thereon for rotation therewith constitutes a cam shaft having afixed eccentricity. Journal mounting of the cams 46, 48 on theirrespective eccentric elements 38, 42 provides a cam shaft having avariable eccentricity. Then, addition of the control means and theabove-described means for drivingly connecting the control means to thecams provides a cam shaft having a selectively variable eccentricity.

One application of my driver 10 is shown in FIGS. 1 and 3. In thesefigures, it will be seen that the driver 10 is journalled for rotationadjacent a shaft 116, one end of the driver 10 being supported asindicated at 118. The shaft 116 is journalled for rotation byconventional means (not shown) and a pair of longitudinally spaced-apartone-way clutches 120, 122 is mounted on the shaft. Such one-way clutchesare well known in the art and need not be discussed, in detail, in thisdescription. For instance, a simple one-way clutch may comprise an innerrace which' carries a ratchet wheel and which may be keyed to the shaft116 and an outer race which carries a pawl for engaging the ratchetwheel and driving it in one direction.

An arm 124, 126 is mounted on the outer race of each one-way clutch 120,122 to extend outwardly and downwardly therefrom as illustrated in FIGS.1 and 3, the arm 124 being arranged to engage the outer peripheralcontour of the cam 46 and the arm 126 being arranged to engage the outerperipheral contour of the cam 48. As illustrated in FIG. 3, a leafspring 128, 130 may be utilized to urge yieldably each arm 124, 126 intoengagement with the outer peripheral contour of its respective cam 46,48. These leaf springs 128, 130 may be supported at their upper ends asindicated at 132 in FIG. 3.

Assuming that the shaft 12 is driven at a constant speed, it will beseen that the shaft 116 will be driven at a speed which is determined bythe position, i.e., the eccentricity, of each of the cams 46, 48. If thecams are positioned so that the axes of their outer peripheral surfacescoincide with the axis of the shaft 12, the arms 124, 126 will not bedriven to impart rotational movement to the shaft 116. Specifically, theamount that each arm 124, 126 is driven depends on the eccentricity ofits associated cam 46, 48. Of course, the speed of the shaft 116 isdirectly dependent upon the amount of movement of each arm 124, 126.

I have shown a bearing 136 mounted on the flange 104 of the sleeve 92,this bearing providing means for axially moving the sleeve in order toposition the earns 46, 48. It will be understood that this bearing 136,the inner race of which is mounted directly on the flange 104, is merelyillustrative and that many means may be provided for pushing and pullingthe sleeve 92 axially along the shaft 12.

Another application of my driver is shown in FIG. 4. Referring to FIG.4, it will be seen that I have illustrated four pumps 138 which areradially equally spaced about the axis of the shaft 12, two of the pumpsbeing shown in section to facilitate this description. Each pump 138comprises means defining a cylinder 140 in which a iston 142 is arrangedfor axial reciprocation, an input valve 144 and a delivery valve 146,these valves being conventional, and a spring 148 for yieldably urgingthe piston 142 in one direction in the cylinder. In FIG. 4, it will beseen that each of the pistons 142 is yieldably urged toward the axis ofthe shaft 12 to be engaged and reciprocated by the cams 46, 48. Thestroke of each piston 142 is thus controlled by the eccentricity of eachcam 46, 48 and can be varied from zero when the axes of the outerperipheral surfaces of the cams coincide with the axis of the shaft 12to a maximum which is equal to the maximum eccentricity of the earns 46,48. It will be apparent that, in order for the eccentricity to be zero,the eccentricity of each cam 46, 48 must be equal to the eccentricity ofthe element 38, 42 on which the cam is mounted.

In the embodiment of FIG. 4, two of the pistons142 will be fullyextended when the other two pistons are fully retracted. I believe thatthe system illustrated in FIG. 4 can ideally be used as a pumping systemfor a fuel injection system for a four cylinder Diesel engine. Eachpiston 142 is reciprocated twice during each revolution of the shaft 12.

What is claimed is:

1. A driver comprising a shaft, a cylindrical element eccentricallymounted on said shaft for rotation therewith, the axis of said elementbeing parallel to the axis of said shaft, a cam journalled on the outerperipheral surface of said element, first means mounted on said shaftfor rocking movement about the axis thereof, second means for drivinglyconnecting said cam to said first means whereby rocking of said firstmeans rocks said cam about the axis of said element, and control meansfor selectively and rockably positioning said first means about 6 saidshaft, said control means being operatively connected to said firstmeans, said control means including a sleeve telescopically disposed onsaid shaft, said sleeve having an elongated slot formed therein andinclining spirally about the axis of said shaft, a pin carried by saidshaft and extending outwardly into sliding engagement with said slot,and third means for drivingly connecting said sleeve to said firstmeans.

2. A driver as in claim 1 wherein said third means includes a secondsleeve with which said first-mentioned sleeve is telescopically related,said second sleeve being provided with a second elongated slot, and asecond pin carried by said first-mentioned sleeve and extending intosaid second slot.

3. A driver as in claim 2 wherein said second slot is inclined spirallyabout the axis of said shaft so that axial movement of saidfirst-mentioned sleeve produces rocking movement of said second sleeverelative to said first-mentioned sleeve and in the same direction as therocking movement of the first-mentioned sleev 4. A driver comprising ashaft, a cylindrical element eccentrically mounted on said shaft forrotation therewith, the axis of said element being parallel to the axisof said shaft, a cam journalled on the outer peripheral surface of saidelement, first means mounted on said shaft for rocking movement aboutthe axis thereof, second means for drivingly connecting said cam to saidfirst means whereby rocking of said first means rocks said cam about theaxis of said element, and control means for selectively and rockablypositioning said first means about said shaft, said control means beingoperatively connected to said first means, said control means includinga sleeve telescopically disposed on said shaft, a first pin rigidlymounted on said shaft to extend outwardly therefrom, said sleeve havingan elongated slot formed therein for slidably engaging said pin, anothersleeve telescopically related with said first sleeve, a second pinrigidly mounted on one of said sleeves and a second elongated slotformed in .the other of said sleeves for slidably engaging said secondpin, at least one of said slots being spirally inclined about the axisof said shaft so that axial movement of said first-mentioned sleeveproduces a rocking movement of said second-mentioned sleeve.

5. A driver comprising a shaft, a cylindrical element eccentricallymounted on said shaft for rotation therewith, the axis of said elementbeing parallel to the axis of said shaft, a cam journalled on the outerperipheral surface of said element, first means mounted on said shaftfor rocking movement about the axis thereof, second means for drivinglyconnecting said cam to said first means whereby rocking of said firstmeans rocks said cam about the axis of said element, and control meansfor selectively and rockably positioning said first means about saidshaft, said control means being operatively connected to said firstmeans, said control means including a pair of sleeves mounted on saidshaft for rotation therewith, said sleeves being telescopically relatedand one of said sleeves being axially movable relative to said shaft, aradially outwardly extending first pin rigidly mounted on said shaft,the axially movable sleeve having an elongated slot formed therein forslidably engaging said first pin, a second radially extending pincarried by one of said sleeves and the other of said sleeves beingformed with a second elongated slot for slidably engaging said secondpin, and at least one of said slots being inclined spirally about theaxis of said shaft so that reciprocable movement of the axially movablesleeve produces a rocking movement of the other sleeve, said othersleeve being connected to said first means.

6. A driver comprising a shaft, a cylindrical element eccentricallymounted on said shaft for rotation therewith, the axis of said elementbeing parallel to the axis of said shaft, a cam journalled on the outerperipheral surface of said element, first means mounted on said shaftfor rocking movement about the axis thereof, second means for drivinglyconnecting said cam to said first means whereby rocking of said firstmeans rocks said cam about the axis of said element, and control meansfor selectively and rockably positioning said first means about saidshaft, said control means being operatively connected to said firstmeans, said control means includes a pair of members mounted on saidshaft for rotation therewith, said members being arranged for relativeaxial movement, a radially extending pin carried by one of said members,and the other of said members being formed with an elongated slot forslidably engaging said pin, said slot being spirally inclined about theaxis of said shaft, and one of said members being operatively connectedto said first means and oscillable about the axis of said shaft.

7. A driver comprising a shaft, a cylindrical element eccentricallymounted on said shaft for rotation therewith, the axis of said elementbeing parallel to the axis of said shaft, a cam journalled on the outerperipheral surface of said element, first means mounted on said shaftfor rocking movement about the axis thereof, second means for drivinglyconnecting said cam to said first means whereby rocking of said firstmeans rocks said cam about the axis of said element, and control meansfor selectively and rockably positioning said first means about saidshaft, said control means being operatively connected to said firstmeans, said first means including a disc carried by said shaft, saiddisc having an outwardly extending, elongated slot formed therein, andwherein said second means comprises a pin rigidly mounted on said camand arranged slidably to engage said slot.

8. A driver comprising a shaft, a cylindrical element eccentricallymounted on said shaft for rotation therewith, the axis of said elementbeing parallel to the axis of said shaft, a cam journalled on the outerperipheral surface of said element, first means mounted on said shaftfor rocking movement about the axis thereof, second means for drivinglyconnecting said cam to said first means whereby rocking of said firstmeans rocks said cam about the axis of said element, and control meansfor selectively and rockably positioning said first means about saidshaft, said control means being operatively connected to said firstmeans, said first means including means carried by said shaft andproviding a guide means extending outwardly therefrom, and wherein saidsecond means comprises slide means carried by said cam and cooperativelyengaged with said guide means.

9. A driver as in claim 8 wherein said control means includes a pair ofmembers mounted on said shaft for rotation therewith, said members beingarranged for relative axial movement, one of said members beingconnected to said first means and oscillable about the axis of saidshaft, a radially extending pin carried by one of said members and theother of said members being formed with an elongated slot for slidablyengaging said pin, said slot being spirally inclined about the axis ofsaid shaft.

10. A driver as in claim 8 wherein said control means includes a pair ofsleeves mounted on said shaft for rotation therewith, said sleeves beingtelescopically related and one of said sleeves being axially movablerelative to said shaft, a radially outwardly extending first pin rigidlymounted on said shaft, the axially movable sleeve having an elongatedslot formed therein for slidably engaging said first pin, a secondradially extending pin carried by one of said sleeves and the other ofsaid sleeves being formed with a second elongated slot for slidablyengaging said second pin, and at least one of said slots being inclinedspirally about the axis of said shaft so that reciprocable movement ofthe axially movable sleeve produces a rocking movement of the othersleeve and said other sleeve being connected to said first means.

11. A driver as in claim 7 wherein said control means includes a sleevetelescopically disposed on said shaft, said sleeve having an elongatedslot formed therein and inclining spirally about the axis of said shaft,a pin carried by said shaft and extending outwardly into slidingengagement with said slot, and third means for drivingly conmeeting saidsleeve to said first means, said third means including a second sleevewith which said first-mentioned sleeve is telescopically related, saidsecond sleeve being provided with a second elongated slot, a second pincarried by said first-mentioned sleeve and extending into said secondslot, said second slot being inclined spirally about the axis of saidshaft so that axial movement of said firstmentioned sleeve producesrocking movement of said second sleeve relative to said first-mentionedsleeve and in the same direction as the rocking movement of thefirstmentioned sleeve.

12. The combination of a pump comprising a cylinder and a pistonarranged for axial reciprocation in said cylinder, and a drivercomprising a shaft, a cylindrical element eccentrically mounted on saidshaft for rotation therewith, the axis of said element being parallel tothe axis of said shaft, a cam journalled on the outer peripheral surfaceof said element, first means mounted on said shaft for rocking movementabout the axis thereof, second means for drivingly connecting said carnto said first means whereby rocking of said first means rocks said camabout the axis of said element, and control means for selectively androckably positioning said first means about said shaft, said controlmeans being operatively connected to said first means, said piston beingengaged with the peripheral contour of said cam to be reciprocatedthereby.

13. The combination of a plurality of pum s, each pump comprising acylinder and a piston arranged for axial reciprocation in said cylinder,and a driver comprising a shaft, a cylindrical element eccentricallymounted on said shaft for rotation therewith, the axis of said elementbeing parallel to the axis of said shaft, a cam journalled on the outerperipheral surface of said element, first means mounted on said shaftfor rocking movement about the axis thereof, second means for drivinglyconnecting said cam to said first means whereby rocking of said firstmeans rocks said cam about the axis of said element, and control meansfor selectively and rockably positioning said first means about saidshaft, said control means being operatively connected to said firstmeans, said pumps being radially disposed about said shaft with each ofsaid pistons being engaged with the peripheral contour of said cam to bereciprocated thereby.

14. The combination of a second shaft, clutch means mounted on saidsecond shaft and arranged to move said shaft in one direction only aboutits axis in response to oscillation of said clutch, follower meansconnected to said clutch means, and a driver comprising a shaft, acylindrical element eccentrically mounted on said shaft for rotationtherewith, the axis of said element being parallel to the axis of saidshaft, a cam journalled on the outer peripheral surface of said element,first means mounted on said shaft for rocking movement about the axisthereof, second means for drivingly connecting said cam to said firstmeans whereby rocking of said first means rocks said cam about the axisof said element, and control means for selectively and rockablypositioning said first means about said shaft, said control means beingoperatively connected to said first means, said follower means beingcooperatively engaged with the peripheral contour of said cam.

15. The combination of claim 14 wherein said second shaft is generallyparallel to said first-mentioned shaft, and spring means yieldablyurging said follower means into engagement with the outer peripheralcontour of said cam.

'16. A driver comprising a shaft, a cylindrical element eccentricallymounted on said shaft for rotation therewith, the axis of said elementbeing parallel to the axis of said shaft, a cam journalled on the outerperipheral surface of said element, first means mounted on said shaftfor rocking movement about the axis thereof, second means for drivinglyconnecting said cam to said first means whereby rocking of said firstmeans rocks said cam about the axis of said element, and control meansfor selectively and rockably positioning said first means about saidshaft, said control means being operatively connected to said firstmeans, a second cylindrical element eccentrically mounted on said shaftfor rotation therewith, the axis of said second element being parallelto the axis of said shaft, 21 second cam journalled on the outerperipheral surface of said second element, and third means providing adriving connection between said cams so that movement of saidfirst-mentioned cam about the axis of said first-mentioned elementproduces a similar movement of said second cam about the axis of saidsecond element.

17. A driver as in claim 16 wherein said third means includes a discjournalled on said shaft and disposed between said cams, an axiallyextending pin rigidly mounted on each of said cams to extend toward saiddisc, and said disc being provided with an outwardly extending slot forslidably engaging each of said pins.

18. A driver as in claim 17 wherein said cylindrical elements areidentical in diameter and diametrically oppositely and equally spacedfrom the axis of said shaft, wherein said cams have cylindrical outerperipheral sur-' faces which are equal in diameter, said cams beingeccentrically journalled on their respective cylindrical elements,wherein said slots in said disc are radially outwardly extending andperipherally spaced apart 180,

to the eccentricity of said element on which said cam is journalled sothat, in one position of said first means, the

axes of said outer peripheral surfaces of said cams coincide with theaxis of said shaft.

References Cited UNITED STATES PATENTS 859,866 7/1907 Atkins 745711,875,854 9/1932 Cooper 2,051,783 8/1936 Dake 74-57l XR 2,067,399 1/1937 Hughes. 2,592,237 4/ 1952 Bradley. 2,900,839 8/ 1959 Mackintosh.3,199,361 8/1965 Prins 74-124 3,373,936 3/1968 Purtell 74124 XR3,374,683 3/1968 Jesse 74571 XR FRED C. MATTERN, JR., Primary ExaminerF. D. SHOEMAKER, Assistant Examiner

